Treatment of silk and composition therefor



Patented Apr. 22, 118241.

UNHTEE S hdlhzzt EDGAR S. GENSTEIN, OF NEW YORK, l\T. ll, ASSIGNOR TOKEIVI PRODUCTS COMPANY, A CORPORATION OF NEW JERSEY.

TREATMENT OF SILK AND COMPOSITION THEREFOR.

N 0 Drawing.

To all whom it may concern:

Be it known that EDGAR S. GENSTEIN, a citizen of the United States,residing at 412 West 129th Street, New York city, in the county of NewYork and State ofNew York, has invented certain new and usefulImprovements in the Treatment of Silk and Composition Therefor, of whichthe following is a specification.

This invention relates to the treatment of raw silk whereby the silk ismade to retain its strength and is prevented from hardening during themanufacturing operations. lit relates also to a composition of matterfor treating fibres of silk, etc.

Raw silk contains a natural gum to the extent of 18 to 22% introduced bythe silk worm during the spinning of the cocoon. lit is desirable toretain this gum throughout the manufacturing operations such as winding, spinning, doubling, warping and weaving, due to the fact that itlends to the silk added strength and keeps the fibres closed. This gummust, however, be removed as, for example, by being boiled 03 previousto the dyeing of the silk in order to obtain level or smooth and evenshades. While giving the advantage mentioned, the gum tends, on theother hand, to stiffen the natural fibre and make it wiry which preventsthe manufacturing operations from being performed with ease. For thisreason, it is customary so to treat some grades of raw silk as tointroduce an oil which will soften the gum. The process in vogue formany years hasbeen to immerse raw silk in a bath containing an emulsionof an oil such as neats-foot oil and soap, for instance, olive oil soap.Other similar baths have been prepared through the use of variouscompounded oils as, for instance, a compound of animal, vegetable andmineral oils in varying proportions similarly emulsified with which totreat silk, or a direct emulsion of an oil previously treated withammonia or alcohol or a straight oil or compounded oil emulsified withan alkaline salt such as sodium or potassium carbonate. The direct useof a sulfonated oil has also been attempted without particular success.

In the case of the old method of using neats-foot oil and soap, the soapperforms only one function, namely, that of producing the emulsion andis really an economic Application filed January 16, 1923. Serial No.613,049.

waste and interferes with the processing of the silk through depositingsoap thereon. The use of an alkaline salt for an emulsification purposeis troublesome owing 'to the fact that local conditions of waterhardness necessitates changes in formula as well as the fact that thetype of mechanical equipment used seems to have a bearing upon thequantities necessary. Either ammonia or alcohol are similarlydisadvantageous as the emulsion produced is only very temporary and isbroken up by the evaporation of the ammonia oralcohol, the former at thesame time producing a disagreeable odor and an objectionable conditionin the silk. Either of these two products also have a penetrating andsolvent action on the gum in the silk which is undesirable. The use of asoluble oil such as a sulfonated oil has not hitherto been successfulowing to the fact that sulfonation seems to change a nondrying oil toone of a drying or semi-drying character Upon the evaporation of thephysical moisture that was introduced while the silk was in the soakingbath, the oil begins to dry producing a harsh and gluey condition in thesilk.

By the present invention raw silk may be so treated that it will retainits strength and will be prevented from becoming wiry during themanufacturing operations. At the same time the disadvantages aboveenumerated may be overcome. It is desirable for this purpose to use acomposition or mixture of ingredients which will overcome the objectionsheretofore encountered, which will not produce any deleterious effectupon the silk, and which can be readily removed so as not to interferewith the dyeing operation. For this purpose a mixture comprising ahygroscopic agent and a sulfonated vegetable or animal oil or a mixtureof two or more of such oils may be used.

The sulfonation of the oil may be effected by treatment with sulfuricacid in ways already well known, which constitutes no part of thepresent invention. A large variety of oils may be used for this processsuch, for example, as cocoanut, neats-foot, olive, soya bean, peanut,corn, palm and lard, preference usually being given to the first threeor four just named.

The hygroscopic agent to be employed may likewise present a wide varietyof choices, the most satisfactory thus far employed being glycerine or aglycerol or a mixture of the same. Hygroscopic metallic salts such asmagnesium chloride or calcium chloride, for example, give rise to thedanger of small crystalline masses of the same being deposited upon andsubsequently cutting or injuring the fibres, and for this reason anamorphous hygroscopic agent should be used.

The sulfonated oil and the hygroscopic agent are introduced into anaqueous vehicle and become dissolved with a portion of the oil remainingvery probably in colloidal suspension therein. The raw silk which may beabout one fifth natural gum, more or less, is immersed in the solutionand retained therein for a period of time Suficiently long to enable thedesired amount of sulfonated oil and hygroscopic agent to becomeadsorbed on the fibres, this period varying somewhat with the nature orqualany the silk and the concentration of the After the silk hasremained in the bath the desired length of time, it is removed and thesurplus water is allowed to drain off or is whizzed off in a centrifuge.The fibres are then carried through the usual winding, spinning,weaving, etc., manufacturing operations to make the cloth, while theyretain their tensile strength. The presence of,

the sulfonated oil keeps the gum soft so that the fibres do not becomewiry and the presence of the hygroscopic material overcomes the tendencyof the sulfonated oil to dry or oxidize thus causing the silk to retainsufiicient moisture to prevent the silk from hardening. The gum andother material that might interfere with the dyeing operation areremoved in the usual way before the dyeing is caused to take place.

The following is given as a specific illustration of the inventionwithout an intention to limit the invention to the particular details orproportions set forth:

.One hundred pounds of raw hardgummed china silk containing about 20% byweight of gum is introduced into a water solution of about 10 pounds ofsulfonated cocoanut oil and three pounds of glycerine, and maintained atabout 80 F., more or less. The amount of water may vary fro-m that justsufficient to cover the silk to several times that amount and the silkmay remain immersed therein from about 30 minutes to twenty hours, thelonger periods of time bemg used with the greater dilutions of the bath,etc. For warp stock a lower temperature and a shorter time of immersionis preferred. In the case of ordinary Japan silk about 5% by weight ofthe sulfonated oil will be found to give good results. In all cases itis generally preferable to enclose the silk in bags to soak it as such aprocedure will in large measure prevent mechanical damage to the fibres.

Some of the advantages of this invention are: The natural gum isretained in the silk and kept soft during the manufacturing operations,the natural fibre retains its pliability and elasticity and is preventedfrom becoming stiff; the weakening of the fibres and their tendency tobecome wiry is prevented; the treating agent can be readily preparedwithout excessive cost; no unstable emulsion with attendant danger ofbreaking down the emulsion is present; the thread is prevented fromhardening on the bobbins; the fibres retain their soft and silky feelregardless of weather conditions; the silk fibres can be kept moist andpliable for as long a time as is desired; the necessity ofv producingoil emulsions is eliminated; the influence of changing temperature andhumidity is minimized; and the treating agent and the gum may be readilyremoved by a boiling soap solution prior to the dyeing of the silk so asto obtain even shades without splotches in the usual way.

I claim:

. 1. The process of treating raw silk which comprises applying to it asulfonated oil and a hygroscopic agent.

2. The process of treating raw silk which comprises applying to it asulfonated Oll and a water soluble, amorphous hygroscopic agent.

3. The process of treating raw silk which comprises applying to it asulfonated oil and a hygroscopic agent of the fatty acid series.

4. The process of treating raw silk which comprises applying to it asulfonated oil and glycerine.

5. The process of treating raw silk which comprises immersing it in anaqueous bath containing a sulfonated oil and a hygroscopic agent.

6. The process of treating raw silk which comprises immersing it in anaqueous bath containing a sulfonated organic oil and a hygroscopicagent.

7. The process of treatlng raw sllk which comprises immersing it in anaqueous bath containing a sulfonated oil, vegetable oil and glycerine.

8. The process of treating raw silk which comprises immersing it in anaqueous bath containing a sulfonated oil, cocoanut oil and glycerine.

9. The process of treating raw silk which comprises immersing it in anaqueous bath containing a sulfonated oil, cocoanut oil and glycerine,the quantity of said oil being about 10% by weight of the quantity ofsaid silk.

10. A composition for treating fibres which comprises a sulfonated oiland a hygroscopic agent.

11. A composition for treating fibres memes;

which comprises a suli'onated oil and a water soluble, amorphoushygroscopic agent.

12. A composition for treating fibres which comprises a sulfonatedorganic oil 5 and a hygroscopic agent.

13. A composition for treating fibres which comprises asulfonatedvegetable oil and a hygroscopic agent of the aliphatic se- 'ries ofcompounds.

14. A composition for treating fibres which comprises a sulfonatedvegetable oil and glyoerine.

In testimony whereof I afix my signature.

EDGAR S. GENSLEIN.

